Trainer Sean Begley, fitness director for Plus One Fitness and one of the biggest firms on Wall Street, designed this workout for überbusy execs. You do three 7-minute circuits and 7 reps of each move in a circuit, completing as many rounds as you can. (Odd numbers engage your mind more than even ones, so you focus less on fatigue.) It's so quick, the big boss will never know you're gone.

Minutes 1 to 7

Works: shoulders, butt, thighs

Pick a weight heavy enough to challenge you for 7 reps. Cycle through the moves for 7 minutes, then take a 1-minute break.

Move 1:Power Squat

Stand with feet hip-width apart, toes turned out, a dumbbell in each hand at shoulders. Squat until thighs are parallel to floor (as shown). Stand as you extend arms to press weights overhead. Return to start; repeat. Do 7 reps.

Minutes 8 to 15

Works: butt, thighs, hamstrings

After your 1-minute breather, immediately start your second circuit. Cycle through the moves for 7 minutes, then take a 1-minute break.

Move 1:Air Lunge

Start in a deep forward lunge on right leg, holding a weight in each hand with arms at sides. Press off right heel to jump up (as shown) and switch legs in midair to land with left leg forward for 1 rep; repeat. Do 7 reps.

Minutes 16 to 23

Works: biceps, butt, thighs, hamstrings

Almost done! Move fast to do as many rounds as possible. And finish strong.

Move 1:Curtsy & Curl

Stand with feet hip-width apart, arms at sides with a weight in each hand, palms in. Lunge right leg back and to left as you curl weights to shoulders, keeping palms in (as shown). Return to start; repeat on opposite side for 1 rep. Do 7 reps.

Minutes 16 to 23

Works: shoulders, chest, abs, obliques, hips

Move 3:Ab-Blaster Push-Up

Start in a push-up, wrists under shoulders, abs engaged and feet together. Do a push-up, then pull left knee toward left elbow (as shown). Return to start; repeat on opposite side for 1 rep. Do 7 reps.